Methods and apparatus to create a panel of media device users are disclosed. An example apparatus includes an interface to receive a unique identifier and an application identifier from a media device executing an instrumented application. A panel creator is to create a master frame corresponding to media devices that have executed the instrumented application. A registration data controller is to: (i) determine a skip rate, (ii) assign the media device from the master frame into a first test cell based on a random value and the skip rate, (iii) select a first recruitment interface associated with the first test cell, and (iv) instruct the instrumented application to, in response to the instrumented application being executed for a first time after a threshold period of time since an initial execution of the instrumented application has elapsed, display the first recruitment interface.